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Ring around neck and soot on shoulders 6ppc

In most cases, yes.
In past years we were ate up on extremely tight clearances, thinking it enhanced accuracy. Much of that line of thinking come out of the old Houston Warehouse experiments when full length sizing and upper load window loads were non existent.

Most agree now that it is better to have a little too much clearance than not enough when it come to overall agging capability in the real world.
Thanks @jackieschmidt. I have wondered about this. So have you found a decrease in accuracy going from let’s say .002 to .003 or more?
 
Thanks for all of the replies. I have a working theory now. Less bearing space of the boattail bullet seated out long into the lands is allowing bullet to move before pressure is building up. This may be further aggravated by not having enough neck clearance but I don’t think so as I have between .0025 and .003 clearance.
Increasing the powder charge helped. See pictures below. Top row is .0025 clearance. Bottom .003.

However, I am not seeing near the velocity that I should with this charge. This lot of N133 is faster than any I have shot so I I don’t think that is the problem. I will try some flat base bullets With more bearing surface and see what happens.
16A5E5E6-D637-4175-AAC6-1A643B5280E7.jpeg
 
Yes. @Ggmac, what does the ring indicate?
The amount indicated by the rings , on both the neck and case are probably the amount of set back . Measure both and see if they are the same . The ring on the neck and the ring on the shoulder that is what im talking about measuring.
 
The amount indicated by the rings , on both the neck and case are probably the amount of set back . Measure both and see if they are the same . The ring on the neck and the ring on the shoulder that is what im talking about measuring.
I’m trying to understand your thoughts on how setting the barrel back could cause this
Could you elaborate?
 
I’m trying to understand your thoughts on how setting the barrel back could cause this
Could you elaborate?
If the barrel setup want exactly thesame as previous barrel setup the runout would show as a ring . It’s possible that a different reamer was used . Ive seen it many times when a 6 ppc tight neck was then increased and set back to a larger neck .
Anytime we set back we risk the chance of not matchingthe previous barrels set up and the ring will show . I hope ive explained this , no coffee yet .
 
I think Ggmac is saying if you don't cut all the neck off lets say 1/8 '' the end of the original neck could show up in the new neck as a ring.
Not the case with longer than neck length set back.
 
If the barrel setup want exactly thesame as previous barrel setup the runout would show as a ring . It’s possible that a different reamer was used . Ive seen it many times when a 6 ppc tight neck was then increased and set back to a larger neck .
Anytime we set back we risk the chance of not matchingthe previous barrels set up and the ring will show . I hope ive explained this , no coffee yet .
You are correct. That is what was done. Went from .262-.268.
 
Well, my thought regarding bearing surface was wrong. The flat base bullets actually shot slower than the boattails.

Ultimately, I have concluded that this barrel (3 groove) is building pressure slower. The increase in powder resolves the problem.

Hopefully I will be able to add enough powder to get to the next node. Below are the two 5 shot groups I shot yesterday. I may try to tune the load in with the tuner. I prefer to get there with powder and seating depth first.

Thanks for all of the replies.
 

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Well, my thought regarding bearing surface was wrong. The flat base bullets actually shot slower than the boattails.

Ultimately, I have concluded that this barrel (3 groove) is building pressure slower. The increase in powder resolves the problem.

Hopefully I will be able to add enough powder to get to the next node. Below are the two 5 shot groups I shot yesterday. I may try to tune the load in with the tuner. I prefer to get there with powder and seating depth first.

Thanks for all of the replies.
What was the load and seating depth from touch for these groups
 
If yo
What is the cause and remedy, if a bullet won't slip into a fired case?

If a bullet will not slip into a fired case, that generally is an indication that your case neck to chamber neck clearance is a little too tight.

When a round fires, the neck expands and releases the bullet. It then shrinks back a little.

if you go back to my post #20, I mentioned that a lot of this idea of really low clearance came from the earlier years of Benchrest, particularly the Houston Warehouse episodes. They were actually sizing necks to where it sprung back each time enough to grip the bullet without neck sizing. A great idea in theory and in an extremely controlled environment, but not very practical for shooting in competition.

The Remedy you are seeking is to simply turn the necks a little thinner.
 
If yo


If a bullet will not slip into a fired case, that generally is an indication that your case neck to chamber neck clearance is a little too tight.

When a round fires, the neck expands and releases the bullet. It then shrinks back a little.

if you go back to my post #20, I mentioned that a lot of this idea of really low clearance came from the earlier years of Benchrest, particularly the Houston Warehouse episodes. They were actually sizing necks to where it sprung back each time enough to grip the bullet without neck sizing. A great idea in theory and in an extremely controlled environment, but not very practical for shooting in competition.

The Remedy you are seeking is to simply turn the necks a little thinner.
The theory being, that the bullet is not being released cleanly?
 
If yo


If a bullet will not slip into a fired case, that generally is an indication that your case neck to chamber neck clearance is a little too tight.

When a round fires, the neck expands and releases the bullet. It then shrinks back a little.

if you go back to my post #20, I mentioned that a lot of this idea of really low clearance came from the earlier years of Benchrest, particularly the Houston Warehouse episodes. They were actually sizing necks to where it sprung back each time enough to grip the bullet without neck sizing. A great idea in theory and in an extremely controlled environment, but not very practical for shooting in competition.

The Remedy you are seeking is to simply turn the necks a little thinner.

What I think:

That and annealing work hardened necks. Springy hard brass even after being turned may exhibit this. Looking at 50 fired rounds, bullets would not slip fit into the sooty necks but would slip into clean fired rounds. Neck walls were consistent thickness. Black stuff was plastered all over bolt face & brass body with tight neck mouths.
 

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